Tunnel kiln



June 17, 1930. P. A. MEEHAN 1,764,460

TUNNEL KILN Filed April 3, 1928 2 SheetS-Sheetl A To NEY June 17, 1930. P. A. MEEHAN 1,764,460

TUNNEL KILN Filed April s, 192s 2 sheets-shea' 2 20` trated and described 2,5 :'FigJQ is a side-elevation with I y Patented June 17, 193()A v PAUL er MEEHAN, QF CLEVELAND, OHIO, assreniro'eivrlamclin DRESSLER'TNEL i .KILNsAINC., on CLEVELAND, QHIo, A comaoRA'rIoNor NEwrYonK n.

TUNNEL Kinn VApplicaten filed Apr1r3,

'= The object of my present invention is to :provide an improved construction'and ar rangement of ,thel provisions for. supplying heatl to the ware'while in the preheating, seci tion of a continuous tunnel kiln.v More specif- Y 'ically, the object o fimy invention is to provide simple and effective provisions for maintaininga positive-circulation of the kiln chamber atmosphere in the'preheating zone and supy.plyng heat to the' circulating gasesin said .Zone `from another portion 'of the kiln.

i [The various lfeatures of novelty which char- Kf Va `3terizeiny invention yare ypointed out with lparticu'l-arity fin the claims annexed to and ifermin'gfal partof-this specification(l For a better'understandingof the inventiomhow-vv` ever7 the ,advantages-possessed by it7 reference j shbuld'be had to 4the accompanying drawings i andv descriptive matter in-which I have illus# preferred embodiments .ofthe invention. i Gfthe'dravvings: j j Fig. l is a section through the kiln taken C :ont-helinel-l ofFigQ; f

n parts ofthe kiln sidewall'broken away; g

. Fig. B isa section on the lline 3-3 of Fig.'2;

y `Figa 4 4is ase'ctgion on the line l-4 of Fig. 2;" @landl fj v j 30 "fFig, 5l isa plan view of one oftheV fan vunitsf 7 fIn-'the drawings Ihave illustrated aportion of a direct fired tunnel' kiln A comprising a f preheatingzone A 'and a furnace'or Vfiring burners-"or Agraftes locatedl in the-sidewall thek kiln chamber A3 towards the entrance of lthekiln where'they are exhausted by suitable i apparatus. :T he' gases in theirb passage through'thepreheating section are yutilized to heat Aware 'mounted'A o n Isuitable v'warel ia'l'l portions of the wareon thev c arsand *ingu Stacks# ,neral` liiow yoverv around'- the" ware 59= *tMyimproved' provisions'for heating'thel in'g gases from the burner `zone-isindicated i mounted in a passageCl :in alignment with;

- fv svzoneA?. The furnace lzeneA2 is heated by thereof and the products combustion theref f frmnorinally'pass longitudinally,through 4supported lonfroller carriers 'locatedbin the .rep-.QV

, G3 therein"connectsthefluefGf withthe im) s 192s. se'riai No.- fzessza."

material in 4the preheating' sectionAcomprise means for maintaining a positive trans-k rect contact withthe ware being"heattreated.'v Y As shown yin Fig; l; the direction ofthe heat@ bythe arrow'a. The kiln is enlargedfonfbeth Y sides of the kiln chamber andprovidedwithc Y' longitudinally `extending lues 5B, eachogf'l which is connected lat'k one end "':to fthe 5 kiln chamber `by spaced herizontal' portsf' adj ai lcent the y'iiue bottom'. i

v`The connectionbetweeneachport@andthe i i iiue vB iS Closed by" damper `slidaloly' port lG- EaCh-Of 'the 'paSSages ,GT is Sealed-t;

- its outer end; The `dampersfDjcangfbe"oper}{y ated byf any; suitablefmechlvnisin (not shown.) extendlngk into the passagesfC.

" Each `flue Bis connected its endadj the entrance end ofthe 'kiln-witha vertical box headg'eifv E into whichv vertical 'of longitudinally extendingpip'es Ff are coni the entrance'`- end `of 'thekilnl The i pipesF* 51 pass thrughf 1a @pluralityy of chambersfffH formed ineach-side wall ofthe kiln and ,whichY are sep ar ated by jbulkheads' 1 Each cham-kv ber is -ofjsubstantially the same cross-sect-io1iv al dimensions as y therfluelB; ll""Vertical,fear#` v rier frames Ffon which the pipes lfare, sup-:lf

ported-are. located adjacent eachbulkheadas l i shown in Fig-3L kEachpplev bank is furthm cesses R' to' permit longitudinal expansionand. @Ontration 0f the pipwlemntsirl QPer-i ation. The-pipes where frequiredrare madev y of cast iron, calorized ,steel orother material; s

suitable for high temperature conditie-iis,v The bottom ofthe header Grl is connecteelgto.v l

suitable exhaust apparatusl-not shownlby a s flue QG', A branch'ii'ue 'G2 havingav damper Chambers-Aa Y v In some cases the platform X may be omitted Y the eXhaust apparatus.

mosphere .horizontal rows, the upper of which is arranged to discharge at a level slightly above the ware supporting platform Xof the kiln car X and the lower row slightly below the platform X as shown in Fig. 3. The'individual nozzles are of the usual Venturi design.

and one or more rows of nozzles arranged to discharge along the floor of the kiln car. Spaced bulkheads S are formed in the wall H? to permit accessV to the interior of the chambers' H.

A pipe K is mounted in the upper portion of the kiln side wall above each of the chambersH as shown in Figs. 2 and 3'. A row of. horizontally spaced Vertical passages H3 en-Y larged at their lower ends extend upwardly from each chamber H to points adjacent the- `corresponding pipe K. Each pipe K is proin Fig. lthe central portion of each pipe Mv isconnected to a corresponding exhaust fan N by a pipe N. Similarly, the pipes K on each side of the kiln chamber corresponding in longitudinal position with the pipe M are connected to the fan N by inclined pipes H4.

The piping arrangement shown is the same' for each pair of chambers along the preheating section of the kiln. Y

With the apparatus shown heating gases from the furnace zone A2 pass toward the en,- trance end of the kiln. Thegases are drawn from* the kiln vchamber through the ports C into the flues B by the suction thereon. The Agases then pass through the bank of'pipes F on each side of the kiln chamber into the headers G, from which they are removed by The kiln chamber atmosphere adjacent each pair of chambers H is drawnupwardly through the pipes M and M by the fan N connected thereto and passed through the fan outlet tothe pipes Kv on each'side of thekiln. The chamber atis then directed downwardly through the openings H3 into the chambers H where it contacts with and absorbs heat from the pipes F carrying the furnace gases. The heated atmosphere is then injected into the kiln chamber through the injector nozzles J. The dampers Dare operated to regulate the flow of furnace gases into the flue B'. Likewise the damper G3 may be opened when f therein for the passageof a longitudinal gas circulation through the preheating zone is desired.

The arrangement of the fan units and the piping system provides a positive transverse circulation of the kiln chamberatniosphere in each .sectionV of the preheating'zone.- While the normal circulation is updraft through the ware and downdraft through the chamber H, the system may be reversed if desirable and a downdraft circulation through the ware positive circulation of the atmosphere in y the Vpreheating zone as describedwould be also present in a muifle fired kiln.

llVhile in accordance withthe provisions of the statutes, I have illustrated and described the best form of embodiment of my invention now known to me, itwill be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention as set fo-rthin the appended Y claims and that in some cases certain features of vmy invention may be used to advantage without a corresponding use of other features. ,l l

Having now described my invention what I claim as new and desireto secure by Letters Patent, is:

1. A tunnel kilnj having a kiln `chamber therein for the passage of ware carrying cars therethrough, a preheating section, a longitudinally extending chamber in the side wall of said preheating section, means for passing heating gases through said wall chamber,` and'separate means providing-a positive cir-v culation of the kiln atmosphere in sai-d preheating section through said wall chamber out of direct contact with said heating ases whereby said atmosphere absorbs heat v rom the heating` gases therein.

2. A tunnel kiln having a kiln chamber therein for the passage of ware supporting cars therethrough, a preheatingsection, a longitu-dinally extending chamber in .the side wall of said preheating section, means for passing heating gases at ahigh temperature in a horizontaldirection through said `wall chamber, and means for passing thekiln atmosphere in said preheating section in a vertical direction throughtsaid wall chamber whereby said atmosphere absorbs heat from the heating gases therein.

3. A tunnel kiln having a kiln chamber ware supporting cars therethrough, a preheating section, a longitudinally extending chamber in the side wall of said preheating section, a bank of pipes mounted in said wall chamber, means forpassing heating gases atV ahigh tempera-Y ture through said pipe bank, and means or circulating the kiln atmosphere in `said pre# heating section through said wall chamber in contact with said pipeswhereby said atmos- -phere absorbs heattherefrom'.

, ,43. A tunnel kiln comprising a preheating section, a longitudinally extending chamber Y in the side wall of said preheating section, injector nozzles connecting the lower portion of said wall chamber with the kiln chamber,

` Y agas distributing pipe above and connected to said wall chamber, a second pipe mounted inthe kiln crown and connected to said kiln '15 chamber, and means connected to said pipes providing a positive circulation of t-he kiln l chamber atmosphere downwardly through n v said wall chamber and out through said nozzles.

y 5. In a tunnel kiln having a kiln chamber @therein for the passage of ware supporting cars therethrough, a preheating section, a plurality of longitudinally extending chambers in the side wall of said section, a plua5 lrality of longitudinally extending pipe mains mounted in said side wall 'above said wall chambers, passages connecting each of said Q .pipes to one of said wall chambers, a plurality of aligned pipes mounted in the kiln crown, a plurality of fans mounted on the top ofsaidkiln, and piping connecting each of said fans with one of said crown pipesand l one of sai-d chamber mains, whereby the kiln atmosphere in different portions of said preheatingl section is positively circulated.

throu h diii'erentfan units.i y 6. direct fired tunnel kiln comprising a preheatingsection'and la furnace section, a

l longitudinally extending flue in the side wall 40 of the kiln, longitudinally spaced ports connecting, the kiln chamber adjacent said, fury f nace section with said flue, a damper located y in each of said ports, a plurality of separate chambers in said side wall, a'bank of pipes 45 extending through said wall chambers, means lg or'drawing heating gases from said furnace i section through said ports and .said iiue into said pipes, a series of pipe mains mounted in said preheatin-g section above the kiln crown l y and connected to the kiln chamber, a second series ofpipe mains mounted above said wall chambers and connected thereto, inj ectorvnvozzles connecting each of said wall chambers'to L 'sai-d kiln chamber, and afan connectedto a pipe main in each -of sai-d series,-a1l of said elements being arranged to provide a positive circulation of the kiln atmosphere in said preheating section through said kiln chamber and around said pipes containing the S0 heating gases.

Signed at Cleveland, in the county of Cuya-` fhoga and State of' Ohio, this 30th day" of` March, A. D. 192e.`

'piss-1 f l PAULAMEEHAN. 

